[Merge][CMake] Merged revisions : 1721

Revision  r1721
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Export PREFIX to find config.h.cmake
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[[Imported from SVN: r1850]]

cmake/pkg/dune-istl-config.cmake.in

@@ -7,6 +7,7 @@ get_filename_component(_prefix "${_dir}/../../.." ABSOLUTE)
 #include("${_prefix}/lib/cmake/@DUNE_MOD_NAME@-targets.cmake")
 
 #report other information
+set(@DUNE_MOD_NAME@_PREFIX "${_prefix}")
 set(@DUNE_MOD_NAME@_INCLUDE_DIRS "${_prefix}/include")
 set(@DUNE_MOD_NAME@_CXX_FLAGS "@CMAKE_CXX_FLAGS@")
 set(@DUNE_MOD_NAME@_CXX_FLAGS_DEBUG "@CMAKE_CXX_FLAGS_DEBUG@")